Earthquake Data and Reports

It is clear that destructive earthquakes pose a continuing major threat to lives and property throughout California. Earthquake strong motion data provide information for engineers to improve earthquake resistance for buildings and other structures. The California Strong Motion Instrumentation Program (CSMIP) records the strong shaking of the ground and in structures during earthquakes for the engineering and scientific communities through a statewide network of strong motion instruments. The measured ground strong shaking is used immediately after an event to assist in emergency response by agencies like Cal OES. Structural measurements are studied after events to analyze the performance of structures, with the goal of mitigating future earthquake impacts through improved building codes for safer, more earthquake resistant structures.

Internet Quick Reports and Internet Data Reports

CISN Internet Quick Report

Strong-motion data for engineering applications after major earthquakes are distributed via the Internet Quick Report (IQR) and the Internet Data Report (IDR) at CGS. The IQR and the IDR are based on the design concept of the traditional Quick Report and is streamlined in an automated fashion. The release of IQR is usually accompanying with the release of ShakeMap and is for earthquakes of magnitude 3.5 or above and for events with strong-motion recordings. The IQR transitions to the IDR after the earthquake.

Center for Engineering Strong Motion Data (CESMD)

CISN Engineering Data Center

The Center for Engineering Strong Motion Data is operated by the California Department of Conservation’s Strong Motion Instrumentation Program (CSMIP) in cooperation with the USGS/National Strong Motion Program (NSMP). A primary goal of the CESMD is to provide rapid information after an earthquake, ranging from the ShakeMap to distribution of the data and calculated parameters.



A ShakeMap is a representation of ground shaking produced by an earthquake. The information it presents is different from the earthquake magnitude and epicenter that are released after an earthquake because ShakeMap focuses on the ground shaking produced by the earthquake, rather than the parameters describing the earthquake source. ShakeMaps are generated automatically following moderate and large earthquakes. These are preliminary ground shaking maps, normally posted within several minutes of the earthquake origin time. Under the CISN project, ShakeMaps currently are generated in both Northern and Southern California and at CGS.

Annual SMIP Seminar Proceedings

SMIP Seminars

The purpose of this annual seminar is to increase the utilization of strong-motion data in improving post-earthquake response, seismic code provisions and design practices. The seminar is a series of annual events designed to transfer recent research findings on strong-motion data to practicing seismic design professionals and earth scientists. The goal is to provide information that will be useful immediately in seismic design practice and post-earthquake response and, in the longer term, in the improvement of seismic design codes and standards.